BACKGROUND:He's the coolest villain around! An escaped convict from the Underwhere, Bonechill invaded the Overthere with his army of Skellobits. He hoped to draw the attention of Mario and the Nimbi girl, Luvbi, who he knew was actually the Pure Heart. Luckily, Mario and Co. put the demonic dragon on ice. Luvbi transformed into the Pure Heart as thanks to Mario.
Strange as it seems, Bonechill was believed to be the greatest Nimbi under Grambi. His ego corrupted him though, and his attempts to overthrow Grambi got him banished to the Underwhere. His growing evil twisted him into the terrible Bonechill.